%%This is a very basic article template.
%%There is just one section and two subsections.
\documentclass[a4paper]{article}

\usepackage{geometry}
%\geometry{left=2.5cm,right=2.5cm,top=2.5cm,bottom=2.5cm}
\geometry{scale=0.8}

\usepackage{graphicx}
\graphicspath{{pic/}}  % picture's path 


\title{Latex Hello Article}
\author{siwind}
\date{July 2014}

\begin{document}
\maketitle
\tableofcontents

\begin{abstract}
	This is a test abstract!
	
\end{abstract}

\section{Introduction}

$$\sum_{i=1}^{5}\sum_{j=i+1}^{5}cos(\theta_i-\theta_j)$$ 

\subsection{Subtitle}

Plain text.

\subsection{Another subtitle}

More plain text.


\end{document}
